1. Field of the Invention
The present invention generally relates to firearms and, more particularly, to gas actuated pistols.
2. Description of the Prior Art
Firearms which utilize for their operation gases which expand therein as a result of burnt propellants are known. The expanding gases are used to cause a slide to move aft for automatic or semi-automatic operation. Among such firearms are pistols, such as the one disclosed in U.S Pat. No. 3,657,960. The known pistols which utilize expanding gas, i.e. gas actuated firearms, include many parts and thus are complicated, difficult to take apart and reassemble, for cleaning or repairing. They are also quite expensive. In addition they are not believed to provide sufficiently high accuracy and reliability. Furthermore they are not designed nor capable of use with reassembling large caliber ammunition such as 0.357 or 0.440 ammo.
All of the known disadvantages of prior art gas operated pistols are believed to be overcome by the novel pistol of the present invention, which is gas actuated. The novel pistol of the present invention can be thought of as comprising:
a frame unit having a front section and a rear section, said front and rear sections terminating in fore and aft ends respectively, said front section being trough shaped defining a pair of spaced apart side walls and a bottom side for forming the bottom of said trough and interconnecting said side walls;
a barrel unit releasably lockable to said frame unit, comprising a barrel defining a bore for a bullet to pass therethrough, said bore having muzzle and breech ends, and front and rear locking members, for engaging said frame unit and be lockable to the front section thereof, said barrel defining a path for gases having one end in communication with said bore proximate the breech end thereof, and extending along said barrel and a second end in communication with an elongated cavity defined in said front locking member, said cavity extending inwardly from an open end in a direction toward the fore end of said barrel unit;
a slidable unit slidable on said frame unit, said slidable unit including a front section shaped to slide under said barrel unit when the latter is locked to said frame unit, and an aft bolt-receiving section, and pressure responsive means at the fore end of said front section adapted to respond to gas pressures in said cavity for applying a force in the aft direction to cause said slide unit to slide aft; and
bias means in contact with said frame and slide units, for applying a fore pressure to said slide unit to urge it toward the front locking member of said frame unit.
As will be described hereafter in detail the front locking member, in addition to the cavity, is shaped so as to wrap around the fore end of the frame unit for added secure interlocking between the barrel and the frame unit. As to the slide unit, it includes a uniquely shaped bridge member which bridges the two slide walls on which the unit slides. The top side of the bridge member is curve-shaped to accommodate the bottom round surface of the barrel so that the slide can slide under it. The bridge member also has a short downwardly pointing bar which is designed to engage a crossbar of a unique biasing unit. The crossbar is slidably supported on two rods on which specially designed coil springs are supported. A specially shaped piston extends fore of the bridge member into the cavity of the front locking member to be subjected to gas pressures therein and to apply an axial force in the aft direction to the bridge member and thus to the entire slide unit which in spite of the spring bias slides aft.
A uniquely shaped bolt which is supported by the slide unit is included.
A novel hammer-driving unit formed as a kit which is releasably securable to the frame unit is included. By means of the hammer-driving unit the length and pressure of the trigger of a two-stage trigger system can be adjusted. Furthermore, the pistol includes a unique arrangement whereby the safety catch provides double safety in that it immobilizes the firing pin as well as disconnects the trigger from the hammer driving unit at the same time.